Koum then hired an old friend who lived in Los Angeles, Chris Peiffer, to make the Black Berry version, which arrived two months later.Whats App was switched from a free to paid service to avoid growing too fast, mainly because the primary cost was sending verification texts to users.
Koum updated Whats App so that each time the user changed their statuses, it would ping everyone in the user's network.
Whats App 2.0 was released with a messaging component and the active users suddenly swelled to 250,000.
Koum visited Acton, who was still unemployed while managing another startup and decided to join the company.
After months at beta stage, the application eventually launched in November 2009 exclusively on the App Store for the i Phone.
On August 24, 2014, Koum announced on his Twitter account that Whats App had over 600 million active users worldwide.
At that point Whats App was adding about 25 million new users every month, or 833,000 active users per day.
Facebook, which was advised by Allen & Co, paid billion in cash, billion in Facebook shares, and an additional billion in restricted stock units granted to Whats App's founders (advised by Morgan Stanley), Koum and Acton.
Whats App Inc., was founded in 2009 by Brian Acton and Jan Koum, both former employees of Yahoo! For the rest of the following years Koum relied on his 0,000 savings from Yahoo! In January 2009, after purchasing an i Phone and realizing that the seven-month-old App Store was about to spawn a whole new industry of apps, he started visiting his friend Alex Fishman in West San Jose where the three would discuss "...having statuses next to individual names of the people," but this was not possible without an i Phone developer, so Fishman introduced Koum to Igor Solomennikov, a developer in Russia that he had found on Rent
in September 2007, the duo traveled to South America as a break from work.
Koum almost immediately chose the name "Whats App" because it sounded like "what's up", and a week later on his birthday, on February 24, 2009, he incorporated Whats App Inc. However, early Whats App kept crashing or getting stuck and at a particular point, Koum felt like giving up and looking for a new job, upon which Acton encouraged him to wait for a "few more months".
In June 2009, Apple launched push notifications, letting developers ping users when they were not using an app.